Hay guys I want too build a 338 on a short action. I am hopeing there is an option out there I have not explored. I was thinking 338-300 wsm but I think there must be a case that will give me more power. What do you know that I dont?

if you want greater powder capacity you will likely need a very good action to build off of. The Fatso (lapua based) would probably give you the edge your looking for otherwize you might look at a Lazzeroni or a possibly a gibbs shortened. However you would be looking at a lot of case prep needed, very expensive brass. Also when you go for the action that you need to handle some of these cartridges you will be heavier than you would have been building an edge and I would guess the performance would be slightly less.

I would be curious to see what the gain would be to go to a 338-270 wsm If that would really work to neck up that much???

__________________
I used to re-load but now I "hand-load".
-- Well, at least I try --

I am not exactly sure just how much length you can get away with. But on Ammoguide it says the 338-300WSM has 79.9 grains of water capacity.

The 338 Ruger compact magnum only has 69.4.

I think that if one could determine what max length possible for short action you might be able to get very creative in forming your own brass, but I doubt you will get much better than the 300wsm as parent cartridge....

The Wyatt is too long but it's parent cartidge is the 416 Rigby. I little more diameter. Perhaps shortening the 416 to the maximum length and necking it to 338. But may be more than action can handle. Thats why I will probably never wildcat something original. I know enough to be dangerous, not enough to actually know what my limits are

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__________________“When a long train of abuses and usurpations, pursuing invariably the same object evinces a design to reduce them under absolute despotism, it is their right, it is their duty to throw off such governments. …” Jefferson

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Custom built 7mm SAUM

Good info guys I have been milling this over for a while. I was under the impression that the 300 wsm would give me more capasitty then the 270 wsm would?

I have a FN wsm action already and that would be the base for the build if I made the decsion to go ahead with something like this.

What about the 325wsm? You may not have to overwork the necks that way. I dont know the first thing about wildcatting, but I would think it would be easier to go from 8mm(325wsm) to 338 than it would be to go from .277 to 338 wouldnt it?